turck 6827380, Instructions For Use Manual

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Integration of the technology modules
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Process output data (PZDA)
The data received from the PLC are loaded into a transmit-buffer in the BL××-1RS485/422 module.
The fieldbus specific transmission for EtherCAT is realized in a 8-byte format which is structured as
follows:

6 bytes are used to contain the user data.

1 byte contains, signals to start the flushing of transmit- and receive buffer.

1 control byte is required to ensure trouble-free transmission of the data.
Meaning of the data bits (process output)
RX_CNT 0-3 This value is transferred together with every data segment. The RX_CNT
values are sequential: The RX_CNT values are sequential:
00

01

10

11

00…
(decimal: 0

1

2

3

0…)
Errors in this sequence show the loss of data segments.
RX_BYTE_
CNT 0-7 Number of the valid bytes in this data segment. In EtherCAT, the data seg -
ments contain a maximum number of 6 bytes of user data.
Fig. 32: Process output data SPS
Designation Value Description
RXBUF FLUSH 0 - 1 The RXBUF FLUSH bit is used for clearing the receive buffer.
If STATRES = 0, 1 or 0
 1:
A request with RXBUF FLUSH = 1 will be ignored.
If RXBUF FLUSH = 1, a rising edge 1
 0 at STATRES clears the transmit buf -
fer.
TXBUF FLUSH 0 -1 The TXBUF FLUSH bit is used for clearing the transmit buffer.
If STATRES = 0, 1 or 0

1:
A request with TXBUF FLUSH = 1 will be ignored.
If TXBUF FLUSH = 1, a falling edge 1

0 at STATRES clears the transmit buf -
fer.
Designation Value Description